Unit 5: Anatomy and Physiology
Homeostasis and the role of Energy
It is important to maintain the healthy function of the body. This report
explains my client’s homeostatic response during and after a standard period
of exercise. With includes collected data of the heart rate, breathing and
temperature.
P5
Homeostatic is the
mechanism inside
our bodies that
regulate and
maintain a stable
and constant
internal
environment as it
keeps our body
working within a
delicate balance.
As homeostatic
ensures that the cells of the body are in the right environment that meets their
needs and allows them to function normally despite external changes. But
nonetheless that this does not mean that there are no changes as they are
continuous fluctuations brought about by variations in both internal and
external conditions including pH and water potential. These changes do occur
around a set point, as homeostasis is the ability to return to that set point to
maintain organism in a balanced equilibrium. Homeostasis is responsible for
body temperature, heart rate, blood pressure, breathing rate, water and
glucose levels.
The waste products including urea and carbon dioxide in the body must be
removed in order to maintain a stable body environment as if they are not
removed, they can interfere with chemical reactions and damage the body.
Homeostasis is described as a negative feedback system, which means that
the corrective action is taken to maintain the constant environment. When an
important variable like the pH of blood and tissue fluid, deviates from the
accepted range of limits, it can trigger responses that return the variable
within a normal range. With a reoccurring negative feedback system of:
1. Corrective mechanisms
switched off
2. Condition in the body change
from set point
3. Change detected
4. Corrective mechanisms
activates
5. Conditions returned to set
point.
The body works in a similar way like the central heating system, which works
to control the temperature in a house. With the system is controlled by a
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,Unit 5: Anatomy and Physiology
thermostat that regulates the temperature and is similar to the hypothalamus,
which monitors and controls the internal environment in the brain. Control
mechanism works like the control of any self-regulating system, which
involves a series of stages, that feature:
1. Set point – the desired level/norm at which the system operates
2. Receptor – the monitor that detects any deviation from the set
point
3. Controller – informs and coordinates information from numerous
receptors
4. Effectors – where the controller sends instructions to it’d
appropriate effector that brings about the changes needed to
return the system to its set point
5. Feedback loop- the effector returns to normality that creates a
feedback loop, which will inform the receptor of the changes to
the system brought by the effector.
Control mechanisms
are coordinated as the
system normally has
receptors and effectors,
as it is important to
ensure that the
information provided by
receptors is analysed
by the control centre
before the action is
taken. And receiving
information from a
number of sources
allows a better degree
of control. An example of coordinated control mechanism is when temperature
receptors in the skin may signal that the skin itself is cold, which will cause the
body temperature to be raised. But the information from the temperature
centre in the brain as they may indicate that the blood temperature is already
above normal. This can arise during strenuous exercise when the blood
temperature rise but sweat will cool the skin. Then the analysing the
information from all detectors, the brain can decide the best course of action,
which would be to not raise the body temperature further in this case. But in
the same way, the control centre must coordinate as the actions of the
effectors can operate cordially like for sweating to become less effective, it
would have to cool the body if it was not accompanied by vasodilation.
M2
1. Homeostatic Mechanisms for Regulation of Heart Rate
Autonomic Nervous System
The Autonomic nervous system controls the involuntary/subconscious
activities of internal organs, muscles and glands. And the system regulates
fundamental states of physiology, which include the heart rate, digestion,
respiratory rate and salivation. This system also sets a balance between
relaxation and excitation required to meet environmental demands. It also
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, Unit 5: Anatomy and Physiology
sets the balance for on-going behaviour for example with foraging for food
and the system is also necessary for short lived ‘emergency’ reactions that
include predator evasion and reproduction.
Somatic Nervous
System
The Somatic
Nervous System
is a part of the
peripheral
nervous system,
which handles
voluntary control
on body
movements and
contains all the
neurons
connected with
skeletal muscles
and skins. And it has two divisions that usually do opposite things in the body
but can sometimes complement each other of:
Sympathetic Nervous System
The Sympathetic Nervous System (SNS) is part of the Autonomic Nervous
System (ANS) as well as the Parasympathetic system (PNS). This system
increases heart rate, blood pressure, breathing rate and pupil size and also
causes the blood vessels to narrow and decrease digestive juices. NIH –
National Cancer Institute. Sympathetic Nervous System. PubMed Health.
[Online] [Accessed on 23rd April 2018]
https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025458/. The
Sympathetic Nervous System prepares the body for physical and mental
activity as it makes the heart beat faster and stronger. As well as open the
airways to allow breathing to come more easily and inhibits digestion.
Parasympathetic Nervous System
The Parasympathetic Nervous System is one of the three divisions of the
Autonomic Nervous System and is sometimes called the rest and digest
system. The PNS conserves energy as it slows the heart rate, dilates blood
vessels, decreases pupil sizes, increases digestive juices and increase
intestinal and gland activity and relaxes sphincter muscles in the
gastrointestinal tract. IH – National Cancer Institute. Autonomic Nervous
System. PubMed Health. [Online] [Accessed on 23rd April 2018]
https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0025459/. The PNS is
responsible for bodily functions where we are at rest as it stimulates digestion
and activates various metabolic processes and it also helps us to relax.
Institute for Quality and Efficiency in Health Care. (2016) How does the
nervous system work?. PubMed Health. [Online] [Accessed on 23rd April
2018] https://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0072574/
Autonomic Nervous System
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